Monoazo dyestuffs



Patented Apr. 27, 1954 -U N-ITEYD STATES PATENT OFFICE MONOAZO DYESTUFFSRudolf .Buegg, Basel, and Heinrich Zollinger,

'Binningen, switzerlandassig-nors to Ciba Limited,'.Basel, Switzerland,a Swiss firm No Drawing. Application November 2, 1951, Serial No.254,647

Claims priority, application. Switzerland November 9, 1950 in which Rrepresents an aromatic radical of the benzene series free from groupsimparting solubility in water and free from hydroxyl groups bound inortho-position relatively to the azo group, Z represents a benzeneradical containing as a substituent at least one saturated hydrocarbonradical having at least 3 and at most s car-bon atoms, and oneXrepresents hydrogen and the other 'X a sulfonic acidgroup. Assaturatedhydrocarbon radicals there are included, together withalkylradicals,also radicals of the a'licyclic series, especiallythe-'cyclohexyl radical.

For the production of such dyestuffs, for example, any desireddiazo-compoun'd of "an aromatic amine of the benzene series free fromgroups imparting solubility in water and containing no hydroxyl group inortho-position to the amino group is coupled with a coupling componentof theformula ample, in a Weaklyalkaline-aqueousmedium with the use ofpara n -propyl, para-isopropyle, paratertiary-amyl-, ormetatertiary-butyl-benzoic This monoacflationmygbe carried out, for ex-2 acid chloride, '2 methyl i tertiary butyl benzoic acid chloride,2:6-dimethyl-4-tertiary .butylbenzoic acid chloride, 4-n-octyl-benzoic.acid chloride, 4- cyclohexy1-benzoic acid chloride or bromide, oradvantageously with 4-tertiarybutyl-benzoic acid chloride.

As 'diazo-componen'ts there may "be psed 'any desired aromatic amines ofthe benzene series which are 'free'from hydroxyl groups'in"orith'oposition to the amino group and from groups "impartingsolubility in'water, that is to say, sulfonic acid groups and carboxylgroups. There "come into consideration, for example, aniline,toluidines, for example, '2-meth'yl-'laminobenzene, xylidines, forexample, 2z4-dimethyl-l-aminobenzene, alkoxyanilines, 'for example, 2'z5-climethoxy-4-c'hloro'l aminobenzene, Z-methoxyl-aminobenzene,2-methoxy-5-tertiary-amyl-laminobenzene, also2-ethyl-l-aminobenzene,4-h- .amyl-l-aminobenzene, 2-methyl-5-isopropyl-laminobenzene, 2 :45-trimethyll -aminobenzene,

' chloranilines, for example, 3-ohloro-1-aminobenzene,2-methyl-5-chloro-1-amindbenzene, and also 4-acetylamino-l-aminobenzene.Especially valuable results are obtained with diazo-compounds fromaminobenzene's, which contain in ortho-position to the amino group analkyl or an alkoxy group, preferably those whichcontain not more than 4carbonatoms, advantageously a methyl, an ethyl or a methoxy group.

These amines can be diazotized by the usual methods, for example, bymeans of sodium nitrite and a mineral acid, and the resulting'diazo-compound coupled with a coupling component of the Formula 2 in analkaline aqueous Especially valuable are the dyestuffs of the Formula l,in which Z represents a benzene radical containing, preferably .inp-position to the CO-group, at least one alkyl group :of 3- -6 carbonatoms.

'The following examples illustrate the invention, the parts andpercentages being by weight.

Example 1 9.3 parts of aniline are diazotized in 30 parts ofhydrochloric acid of 30% strength and 200 parts of water at C. with asolution of '7 parts of sodium nitrite in 25 parts of Water.

The resulting diazo-solution is added at 0-5 C. in the form of a thinstream to a well stirred solution of 47.9 parts of1-(4'-tertiary-butylbenzoylamino) -8-hydroxynaphthalene-3 6-disulfonicacid and 50 parts of sodium carbonate in 500 parts of water. When thecoupling reaction is complete the dyestufi formed is separated byfiltration and dried. It is a red-brown powder, which dissolves in waterwith a red coloration and dyes wool from an acetic acid bath bright redtints having excellent properties of wet fastness.

The 1- (4'-tertiary-butyl-benzoylamino) 8-.hydroxynaphthalene-3:6-disulfonic acid may be prepared as follows:

319 parts of 1-amino-8-hydroxynaphthalene- 3:6-disulfonic acid aresuspended in 1500 parts of water and dissolved by the addition of 80parts of sodium hydroxide. There are so added simul- 'taneously to thesolution at 30-40 C. in the course of hours 260 parts ofparatertiary-butylbenzoyl chloride and 200 parts of sodium carbonatewhile stirring well that the mixture always has a weakly alkalinereaction to phenolphthalein. 30-40 C. for 2 hours, and then at 90-95 C.for a further 2 hours. The whole is then allowed to cool to C., andafter 20 hours the precipitated product is separated by filtration. Ifnecessary, for the purpose of purification the product a is dissolved inhot water and decolorized by the addition of active carbon. Afterfiltering off the carbon the product is reprecipitated by the additionof a saturated solution of sodium cloride.

There is obtained after filtering and drying the disodium salt ofl-(4tertiary-butyl-benzoyl amino) 8 hydroxynaphthalene-3:S-disulfonicacid in the form of a pale grey powder which dissolves in water to givean almost colorless Example 2 15.0 parts of i-acetylamino-l-aminobenzeneare diazotized in parts of hydrochloric acid of 30% strength and 200parts of water at 0 C.

v with a solution of 7 parts of sodium nitrite in 25 parts of water.

,. The diazo-solution so obtained is added at 0 -5 C. in the form of athin stream to a well I stirred solution of 47.9 parts of1-(4-tertiarybutyl-benzoylamino) 8 hydroxynaphthalene- 3:6-disulfonicacid and parts of sodium carbonate in 500 parts of water. When thecoupling reaction is complete, the dyestufi formed is separated byfiltration and dried. It is a dark powder, which dissolves in water witha bluishred coloration and dyes wool from an acetic acid bath abrilliant ruby red tint having excellent wet fastness properties.

By using in this example 10.? parts of 2- methyl-l-aminobenzene, insteadof 15.0 parts of i-acetylamino-l-aminobenzene, there is obtained adyestufi which dissolves in water with a bluishred coloration and dyeswool from an acetic acid The temperature is maintained at4-ch10ro-2:5-dimethoxyaniline.

bath brilliant red tints having excellent wet fastness properties.

Example 3 A diazo-solution prepared in the usual manner from 6.2 partsof 2-ethy1-1-aminobenzene is introduced dropwise at 0-5 C. into asolution of 27 parts of the disodium salt of1(4-tertiarybutyl-benzoylamino) 8 hydroxynaphthalene- 3:6-disulfonicacid in 400 parts of water to which there were previously admixed 200parts of a sodium carbonate solution of 10% strength. There is obtaineda blue-red dyestuff which is separated by filtration after a few hours,and, if desired, is purified by dissolution in hot water and partialsalting out. The dried dyestuff is a blue-red powder which dissolves inwater with a blue-red coloration and in concentrated sulfuric acid witha violet coloration. The dyestuff dyes wool from an acetic acid bathpure blue-red tints having good properties of fastness to washing andlight. In its free acid state it corresponds to the formula can HQ Nnoo(1341B; 1 l l By using 1- (4'-tertiary-buty1-benzoylamino)8-hydroxynaphthalene-4:fi-disulfonic acid, instead of 1-(4-tertiary-butyl-benzoylamino) -8- hydroxynaphthalene-3z6-disulfonicacid, there is obtained a more yellowish dyestufi having similarproperties.

Example 4 is filtered off after a few hours and is washed with coldwater, and then dried. There is obtained a blue-red powder whichdissolves in water and in concentrated sulfuric acid with a blue-redcoloration and dyes wool from an acetic acid bath pure bluered tintswhich are very fast to washing and fulling.

Example 5 To a solution of 27 parts of the disodium salt of1-(4'-tertiary butyl benzoylarnino) 8 hydroxynaphthalene-3zd-disulfonicacid in 400 parts of water, mixed with 200 parts of a sodium carbonatesolution of 10 per cent strength, there is added dropwise at 0-5 C. thediazo solution prepared in the usual manner from 9.4 parts of A violetdyestufi forms immediately and is separated by filtration after a fewhours and then dissolved in hot water for purification. The hot solutionis clarified and the greater part of the dyestuif precipitated by theaddition of saturated sodium chloride solution to the hot solution. Thedyestuif is then filtered and. dried. It is a blue-red powder whichdissolves in water with a violet coloration and in concentrated sulfuricacid with a blue coloration and dyes wool from an acetic acid bath pureviolet tints fast to washing and light.

By using 9.7 parts of 2-amino-1-methoxy-4- tertiary amyl benzene in lieuof 9.4 parts of 4- chloro-Z:5-dimethoxyaniline, a dyestuff is obtainedwhich after drying is a blue-red powder and dissolves in hot water witha blue-red coloration and in concentrated sulfuric acid with a bluecoloration. In its free acid state it corresponds to the formula OCH3CH3 HOaS and dyes wool from an acetic acid bath blue-red tints of goodlight fastness and particularly good fastness to washing and fulling.

Ezvample 6 2 parts of the dyestufi obtainable as described in the firstand second paragraphs of Example 1 are dissolved in 4,000 parts ofwater, 10 parts of crystalline sodium sulfate are added to the dye bath,and 100 parts of wool are entered at 40-50 C. 3 parts of acetic acid of40% strength are then added, the whole is raised to the boil in thecourse of half an hour, and dyeing is carried on at that temperature forof an hour. After rinsing and drying there is obtained a brilliant reddyeing having very good properties of wet fastness.

What we claim is:

1. A monohydroxymonoazo dyestuff which in the state of the free acidcorresponds to the formula no lTIH-CO-Z benzene radical containing onesaturated hydrocarbon group having at least 3 and at most 8 carbonatoms.

2. A monohydroxymonoazo dyestufi which in the state of the free acidcorresponds to the formula Ho H1\ I-oo-C -R,

wherein R represents a benzene radical free from groups impartingsolubility in water and substituted in o-position to the azo group by amember selected from the group consisting of an alkyl group of at most 4carbon atoms and an alkoxy group containing at most 4 carbon atoms andR2 represents a saturated hydrocarbon radical having at least 3 and atmost 8 carbon atoms.

3. The monoazo dyestuff which in the state of the free acid correspondsto the formula 4. The monoazo dyestuff which in the state of the freeacid corresponds to the formula GEE-C132 21-15 OH smooQ-o /CH1 CHz-CHzN=N HOaS- sea 5. The monoazo dyestufi which in the state of the freeacid corresponds to the formula References Cited in the file of thispatent UNITED STATES PATENTS Number Name Date 1,073,902 Julius et alSept. 23, 1913 1,073,904 Julius et a1 Sept. 23, 1913 1,824,686 RichardSept. 22, 1931

5. THE MONOAZO DYESTUFF WHICH IN THE STATE OF THE FREE ACID CORRESPONDSTO THE FORMULA